Please refer to FIG. 1 for the conventional instrument for testing skin moisture. Such instrument comprises a portable casing 100, a ceramic resonator 110 at the front end of the casing 100, a liquid crystal display (LCD) screen 120 on the surface of the casing 100, and a testing circuit inside the casing 100; wherein the testing circuit is coupled to the ceramic resonator 110 and the LCD screen 120. In the test, such device makes use of the ceramic resonator 110 to contact with the skin, which will cause a change of resonance frequency. The measured difference will be sent to the testing circuit for data processing, and the water content of the testing skin can be calculated. The result of such calculation will be displayed on the LCD screen 120, so that the user can know about the test result. However, the manufacturing cost of the ceramic resonator 110 is higher than that of the conventional testing components, and the traditional skin moisture test involves individual requirements and cost to customize the ceramic resonator 110 for the instrument.
In view of the shortcomings of the traditional structure, the inventor of this invention focused on the problem to provide a feasible solution, and conducted extensive research and development, and finally invented the apparatus for testing skin moisture in accordance with this invention.